1. Field of the Invention
This present invention relates generally to swathing systems, and more particularly to a proactive swath planning system having improved capability for assisting and guiding a vehicle operator in swathing a selected geographic area.
2. Description of the Prior Art
Various swathing systems and associated methods of control have been suggested at one time or another, but in each instance, these known swathing systems leave something to be desired. For example, there is a need in the swathing systems industry for a proactive swath planning system that precisely and accurately assists a vehicle operator in guiding the vehicle over a selected geographical area, e.g. farm field, whenever the vehicle traverses a product delivery area. Such a proactive swath planning system is highly desirable in areas where a foam marker cannot be readily applied, such as in wheat fields, or when operating at night. For example, it is possible to increase the production capability of certain vehicles significantly through the efficient application of a swathing system. Global Positioning System (GPS) designers and users including, but not limited to those in the agricultural community, have not yet recognized the necessity for providing a proactive swath planning system. This problem has been totally ignored by the swathing products industry because the focus of this industry has been concentrated on machines and associated reactive methods to assist a vehicle operator in guiding the vehicle in response to the amount of distance the vehicle moves away from a planned path, in contradistinction with the aforesaid highly desirable proactive swath planning system.
Numerous different types of swathing systems are available today. These systems may include a pull type unit (towed) or a self-propelled unit. Presently, these systems do not provide a proactive means to assist and guide a vehicle operator along a predetermined swathing path. These known systems do provide a way to assist the vehicle operator in returning the vehicle to a predetermined swathing path as the vehicle moves away from the aforesaid predetermined swathing path. As stated above, they do not provide any proactive information to assist and guide a vehicle operator in a manner that accurately and precisely ensures and maintains the vehicle on a predetermined swathing path. Present swathing system designs generally incorporate the use of precise digital GPS signals to guide the vehicle when in the field. Most often, this is accomplished through the use of a real-time kinematic (RTK) differential GPS and a light bar. These systems guide the operator by displaying on the light bar, the displacement of the vehicle from the intended line of travel. An obvious limitation of this type of system is the need to follow a straight line for proper swathing. This is clearly impossible in a large number of fields, and therefor renders this technique of swathing useless in those instances. It would be of significant use to have a swath planning system enabling the parallel generation of curved path lines. Such a swath planning system would allow a more diverse field condition to be addressed by the swathing system. Another limitation of the aforesaid known swathing systems embraces the nature of the information presented to the vehicle operator. As stated herein above, this information is presented in a light bar format, and consists of a lateral measure signifying the distance off-line the vehicle operator is presently driving This approach results in a system that enables a reactive driver to drive towards the preferred line of travel, but does not allow or provide a great deal of advance, or proactive information. It is therefore desirable to provide the operator a planned path for the vehicle, providing forward data that would reduce the total amount of cumulative error.
In view of the above, it is highly desirable to provide a parallel path swath planning system which will allow a curving path to be input to the system for parallel path generation and allow vehicle steering based upon the position the machine is in, rather than the position it should be in.
U.S. Pat. No. 5,615,118, issued Mar. 25, 1997, to Frank, entitled Onboard Aircraft Flight Path Optimization System, discloses a performance management computer, a control display unit, an infrared probe, a temperature probe, a weather radar, an inertial navigation system, and comparing apparatus to achieve an altitude that has less head wind and is therefore more economically efficient. U.S. Pat. No. 5,606,850, issued Mar. 4, 1997, to Nakamura, entitled Outdoor Working Automating System discloses a rice reaper that includes an automated working system that causes a memory to store a route previously traversed by the rice reaper. U.S. Pat. No. 5,471,574, issued Nov. 28, 1995, to Prasad, entitled Improved Method For Displaying A Computer Generated Graphic On A Raster Output Scanner, discloses a method to determine if parallel lines can be developed for an entire trajectory. U.S. Patent Number 5,459,820, issued Oct. 17, 1995, to Schroeder et al., entitled Method For Graphical Display Of Three-Dimensional Vector Fields, discloses a graphic technique for visualizing 3-D vector data on a graphics computer.
Other exemplary U.S. patents that disclose apparatus and methods directed to automatic control and/or visual display of machine movement include U.S. Pat. No. 5,438,817, issued Aug. 8, 1995, to Nakamura; U.S. Pat. No. 5,414,801, issued May 9, 1995, to Smith et al.; U.S. Pat. No. 5,289,185, issued Feb. 22, 1994, to Ramier et al.; U.S. Pat. No. 4,999,780, issued Mar. 12, 1991, to Mitchell; U.S. Pat. No. 4,860,007, issued Aug. 22, 1989, to Konicke et al.; and U.S. Pat. No. 4,603,753, issued Aug. 5, 1986, to Yoshimura et al.
Modern mobile product applicator machine control systems typically have a host controller located within the operator cab of the machine, including a processor with associated input and output devices. The host is generally directly linked to at least one other controller which may also be located within the cab, and which is responsible for all communication to devices on the machine, such as shown in U.S. Pat. No. 4,630,773, issued Dec. 23, 1986, to Ortlip, entitled Method and Apparatus for Spreading Fertilizer, and U.S. Pat. No. Re 35,100, issued Nov. 28, 1995, to Monson et al., entitled Variable Rate Application System, both assigned to Ag-Chem Equipment Company, Inc. of Minnetonka, Minn., the Assignee of the present invention. The system disclosed in the '100 reissue patent comprises a controller accessing a soil map indicating a soil characteristic for each portion of the field. Field locations and status maps indicating current crop input level at various locations in a field to be treated are monitored by a control system. A crop input map is updated after a dispensing pass to provide a real-time record. Position locators for the machine in the field may include "Dead Reckoning", GPS, or LORAN systems, for example.
U.S. Pat. No. 5,355,815 discloses yet another closed-loop variable rate applicator system. The system operates by determining a soil prescription in near real-time and dispenses crop inputs to the soil scene as a fraction of the soil prescription. The '815 patent is also assigned to Ag-Chem Equipment Company, Inc. and is incorporated herein by reference in its entirety.
Another system is disclosed in U.S. Pat. No. 5,453,924, issued Sep. 26, 1995, to Monson et al., entitled Mobile Control System Responsive To Land Area Maps. This system expands on earlier known applicator machine controls systems including those heretofore assigned to Ag-Chem Equipment Company, Inc., by incorporating a network scheme which links a host controller positioned within the operator cab to multiple controllers located at various points on the machine external to the operator cab. All of the above patents are assigned to the Assignee of the present invention and are incorporated by reference in their entirety herein. The control systems assigned to Ag-Chem Equipment Co., Inc. and referenced herein above describe systems which, when properly configured with the present inventive algorithmic software and associated sensors and feedback devices, may be adapted to practice the present invention.